Dishwasher



IwgjnL June 22, 1954 D. A. MEEKER ET AL WHHHIHIIIH.

Wm Hllul 3 Sheets-Sheet l ATTORNEYS June 22, 1954 A, MEEKER ET AL 2,681,658

DISHWASHER Filed 001;. 11, 1949 3 Sheets-Sheet 2 H0 705 INVENTOR 25 0 L -4 75 BY .4 8O 92 ATTORN EYS Patented June 22, 1954 DISHWASHER David A. Meeker and Russell 0. Geiger, Troy, Ohio, assignors to The Hobart Manufacturing Company, Troy, Ohio, a corporation of Ohio Application October 11, 1949, Serial N0. 120,655

Claims. 1

This invention relates to dishwashers and more particularly to such machines which are adapted for household use and for use in smaller commercial installations.

In machines of this character, the soiled dishes or other articles are placed in a washing chamber and subjected to the action of washing sprays. The wash water is recirculated for a period of time sufficient to loosen and remove the food particles on the articles, such food particles being carried along with the wash fluid. While it is important to provide for such fluid recirculation, it is undesirable to allow the food particles themselves to be recirculated, particularly the larger sized particles thereof.

In accordance with the present invention, therefore, a simple and effective strainer construction is provided which is arranged to overlie a sump in the lower part of the chamber into which the liquid drains, the strainer being such as to collect the food particles on its surface while allowing the fluid with at most only the smaller particles entrained therewith to pass freely therethrough. The strainer is formed with a recessed annular portion which extends downwardly forming an enclosing screen entirely sur rounding and enclosing the drain outlet so that the food particles which collect upon the screen surface are retained within the screen and are forced to collect at the bottom of this recessed area immediately adjacent the drain outlet. The wash liquid meanwhile has been allowed to flow freely into the remainder of the sump lying outwardly of this screen chamber, and the pump which recirculates the wash fluid has its inlet in this outer area so that it picks up the fluid itself with only the smaller entrained materials, but with the larger sized particles being effectively removed therefrom. The central recessed area of the strainer may have a coarse screen mounted above it to collect still larger food particles and prevent the flushing of such materials down the drain, but these perforations are preferably of such size as to allow the passage of practically all particles of normal size.

In the course of the washing operation, therefore, the food particles are continuously withdrawn from the circulating fluid and collected in this inner screen chamber, immediately above the drain opening. Thereafter, at the end of the washing cycle, the operation of the pump is stopped and the drain outlet is opened, providing for immediate flushing of the collected food par ticles down the drain. This provides a self -clean ing strainer assembly which contributes to the production of the dishes in a clean condition, as well as greatly facilitating the maintenance of the dishwasher itself in a clean and sanitary condition.

Maintenance of sanitary conditions is further facilitated by reason of the fact that the strainer assembly and the drain valve structure are readily removable from the sump and may be lifted directly out of the sump through the door opening. The wash arm lifts off of its support on the pump housing, and following removal of these parts the pump housing itself may be directly removed exposing the pump impeller. In this way full and complete cleaning of all of the the parts is greatly facilitated, those which are removed being readily cleaned outside the chamber and the pump impeller which remains being directly and readily accessible through the large door opening so that it may likewise be readily and easily kept in a thoroughly clean and sanitary condition.

It is accordingly the principal object of the invention to provide a dishwasher of this char acter which is simple to operate, easy to maintain in a clean and sanitary condition, and which is highly advantageous and satisfactory in use.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings- Fig. 1 is a side elevation of a dishwasher in accordance with the invention for domestic use, with portions of the cabinet and other parts broken away to illustrate details of internal construction;

Fig. 2 is a perspective view of the dishwasher with the door opened and the racks filled with dishes;

Fig. 3 is a fragmentary perspective View looking at the bottom of the washing chamber through the opened door;

Fig. 4 is a fragmentary View on a larger scale taken in vertical central section through the strainer and pump assembly and the drain outlet and showing the drain outlet closed;

Fig. 5 is a fragmentary exploded view of the parts shown in Fig. 4;

Fig. 6 is a fragmentary view taken as indicated by the line 66 in Fig. 1 and showing the front of the pump housing with a portion thereof broken away to expose the impeller;

Fig. 7 is a fragmentary sectional view showing the drain outlet opened;

Fig. 8 is an enlarged fragmentary section on the line 88 of Fig. 7; and

Fig. 9 is a fragmentary section on the line 9-4? of Fig. 8.

Referring to the drawings, which illustrate a preferred embodiment of the invention, the dishwasher includes an outer cabinet shell l provided with a supporting base l6 and a top il' having a splasher back 68 preferably formed integral therewith. An inner shell or casing 2i? encloses the washing chamber 22 for receiving the dishes to be washed, and a lower shell or casing 23 forms a sump portion 24 of the chamber 22 which is provided with a drain outlet as-. seinbly indicated generally at 25. Access to the dish chamber 22 for loading and unloading dishes is provided through a door 26 at the front of the cabinet hinged on a horizontal axis as shown in Fig. 2 and provided with a handle 2-? and spring counterbalance 28, and it will be noted I that shell 23 extends upwardly above and outwardly of the lower end of the inner liner 29 of door 26. The starting switch handle and an indicator light are shown at 30 and 3!, respectively, at the front of the cabinet, and a sequence timer control has a knob, shown at 33- in Fig. 2, cross reference being made in this connection to our co-pending application, Serial No. 120,656, filed of even date herewith.

Two separate and independent racks are shown for supporting the dishes and other articles to be washed in chamber 22. The lower rack 35 is mounted just above the level of the door hinge line by means of rollers 36 carried by brackets 37 on the sides of the rack and riding on tracks 33 at the sides of inner shell 28. rack id is mounted independently of rack 35 by means of inverted channel-shaped tracks d! secured on either side thereof and riding on rollers 42 carried by the sides of the shell 20. As shown in 2, the lower rack 35 is adapted to carry plates and cooking utensils, and it is also provided with a basket portion 4 at the front for silverware. The upper rack 4i} is intended to receive glasses, cups and the like.

The washing and rinsing fluid enters the washing chamber 222 at &5 (Fig. l) by way of a suitable vaivecontrolled conduit (not shown) operated by the timer to admit the desired amount of fluid. This fluid is then recirculated over the articles by means of a pump assembly in the sump as shown in Figs. 4 and 5. The pump.

motor 53 is provided with a, front bracket El which extends into the sump from the rear through a suitable opening in the lower shell 23 and is clamped in position by means of'a ring .52, gaskets 53 and bolts 56. An impeller 55havmounted by means of a bushing 68 on a stud 5! r set in an internal boss portion $8 of housing (ii and the lower end of the wash arm is flared at $9 to ride on thetapered upper end portion of housing it and provide. a liguid tight seal. The housing (ii? is removablysecur-ed in position over the impeller by means of a pair ofbolts The upper 4 l6 extending forwardly from the bracket 5i and provided with wing nuts ii, a suitable gasket 12 being positioned between the rear edge of the housing and the front face of bracket 5|.

'Thedrain outlet unit 25 is shown in detail in Figs. 4- and 7 to 9. It includes a generally bowl shaped valve body '55 which is clamped to the bottom of shell 23 by means of a flanged collar ll and gasket 18, locating pins l9 being provided to assure that the body will remain in proper angular position, and the lower end of the body is tapped for connection to a drain tube 30. The drain valve is a collar force fitted on the lower end of the overflow tube 86 and provided with a rubber O-ring 8? adapted to seat on the tapered inner surface 88 of collar H to close the drain.

The valve 85 is mounted for vertical movement to open and close the drain. Referring to Figs. '7 to 9, the valve 85 includes a pair of oppositely disposed arms to extending inwardly and downwardly to an integral sleeve 9! slida-bly mounted on a vertical pin 925st in an internal boss portion 93 of the body "55, leaving openpassages 94 on either side of arms 30 for free drainage from the overflow tube 2 6 to drain tube 8i? when valve 85 is in closed position. The sleeve 3! is provided on opposite sides with flats es having shoulders 96 at their lower ends and a circumferential shoulder til above themQand the lower end of sleeve GE is tapered at Q9 on its other pair of opposite sides.

A lever rod M59 is mounted for pivotal movement in a flexible mounting comprising a ring Hit set in a peripheral groove on the rod and held between a pair of rubber washers H22 in an open-ended cap 993 threaded on an extension portion. we of body "55, these washers thus sealing this part of the body against escape of liquid, Two resilient yoke arms 555 are riveted to the inner end of lever lei and are adapted to be received in the flats between the shoulders 85 and 9? as shown in Fig. 8. Thus when the 7 lever its is in the position shown in Fig. 4, the

yoke arms bear against the shoulders 95 and draw the sleeve er and valve 85 downwardly into drain closing position, and when the lever arm tilts to the position shown in Fig. 7, the yoke arms bear against the shoulder 97 and lift the sleeve 5! and valve 85 to open the drain, the overflow tube 85 being raised any; lowered with valve 85. It will als be noted that the shoulders 93 and Q? arerounded to permit yoke arms 565 to rock smoothly over them during movement of the valve 85.

A spring He normally biases the lever It!!! to valve opening position. As shown in Figs. land 5, this spring is generally U-shaped as viewed from above, and it includes coiled portions Ill mounted on cylindrical bosses i l 2 and with their ends received in apertured lugs I 53 at either side of valve body 75. This arrangement thus provides a downward pull on the middle part of the spring which seats on the lever Hit near its outer end. The lever N39 is moved in the opposite direction to valve closing position by means of a solenoid H5 mounted in the front portion of the cabinet and having its plunger yieldably connected with the outer end .of lever 5539 through a spring H6. The solenoid is energized and deenergized through the timer in proper relation with the washing and rinsing cycles to The strainer assembly is arranged to trap food particles from the dishes and prevent such particles from reaching the pump assembly. The main or upper unit of the strainer assembly comprises a centrally dished and generally square perforate upper section I having rounded corners and adapted to seat in the complementary recessed portion I2I of the inner shell 23 to separate the dish chamber 22 from the sump 24. This upper strainer-section I20 is so formed as to slope toward an opening I22 so located as to be approximately concentric with the drain outlet of the sump. It is also formed adjacent one side with an opening I23 to receive the upward portion 62 of the pump housing 60. A middle perforate strainer section I24 is welded at its upper end in the opening I23 and is in turn welded in its lower end to a lower frusto-conical perforate section I25 which forms a funnel extending at its lower end into the valve collar 11. All of these strainer sections have relatively flne perforations for preventing the passage of food particles of such size as to be capable of clogging or otherwise interfering with the action of the impeller or the proper washing and rinsing operations, perforations of the order of inch in diameter having been found satisfactory.

A separate inner strainer I includes an upwardly extending central portion I3I which forms a handle adapted to telescope over the upper end of overflow tube 85, and the lower portion of this which is provided with a curved outer rim I32 adapted to seat removably on the complementary curved portion of the intermediate strainer section I24 and to form an annular trough. The strainer I30 is provided with a series of relatively large holes I33 in its lower portion and a similar ring of holes I34 in its handle portion I3I at approximately the level of the upper end of the overflow tube 86 when valve 85 is in closed position, satisfactory results having been obtained with the holes I33 and I34 approximately 1%; inch in diameter.

In operation, after the racks have been loaded with dishes in the desired quantity and a suitable detergent placed in the washing compartment, the machine is started by means of switch 30 to actuate the timer, which first effects closing of the drain valve and opening of the fill valve to supply wash liquid through the inlet to the. level in sump 24 of the top of the overflow tube 86. The timer then starts the pump motor to drive the pump, and the liquid is drawn up into the intake passage BI by impeller and forced upwardly through outlet passage 62 and wash arm 64 for discharge through the slots 55. As this action continues, the liquid fiows down into the sump through the strainer unit for recirculation, carrying with it the food particles removed from the dishes, and with the upper strainer portion I20 concave as shown, food particles washed from the dishes are carried down toward the strainer funnel portion I25.

The food particles which are too large to pass through the perforations of the strainer assembly are retained upon the upper surface of strainer section I20 and follow the path of the fluid in moving downwardly, passing through the larger perforations I33 of the strainer I30 and into the lower section I25, where they collect immediately above the drain outlet. Meanwhile the washing fluid with only the finely entrained food particles is allowed to flow into the sump portion outwardly of the strainer, and

it is in this area that the pump inlet is located,

6 thus effectively segregating the food particles from therecirculating fluid. The strainer itself thus tends to be self-cleaning with the collected material being located immediately adjacent the drain outlet and in position where it will be flushed out upon the opening thereof. If there are any unusually large sized particles which should not be allowed to flush out through the drain, or if an article of silverware should fall into the sump, it will be caught upon the strainer I30 and can be removed by the operator at the end of the cycle, this being accomplished simply by the lifting out of the strainer portion I30.

It will thus be seen that during the washing operation, any food particles present on the dishes are effectively removed and trapped for ready disposal without being recirculated, the Wash liquid being strained each time before it again reaches the intake 6| of the pump. Then after the washing cycle is completed and the wash liquid discharged, similar rinsing operations follow as controlled by the timer, the rinse water being repeatedly sprayed over the dishes and then strained before further recirculation. Thus not only is proper cleansing of the dishes assured, but also with solid particles disposed of as described, the interior of the cabinet is maintained clean and sanitary.

The construction and arrangement of the strainer and pump units greatly facilitates maintenance of the dishwasher by making possible quick and easy disassembly of these parts. Referring particularly to Fig. 5, the wash arm can be removed by simply lifting it off stud 61, and the strainers I30 and I20 can be similarly lifted out. Next the overflow tube and drain valve can be removed by first twisting them through to release the yoke arms I05 from between shoulders 96 and 97, after which this unit can be lifted out as indicated in Fig. 5. The pump housing 60 will then be fully accessible as shown in Fig. 6, and it can be quickly removed by releasing wing nuts ii to expose the impeller 55. Direct and easy access is thus provided through the large door opening so that the cleaning and repair of the pump impeller are greatly facilitated while the other parts of the pump and the entire strainer assembly are directly removable.

Reassembly of these parts is equally simple by following the reverse sequence of steps, and it will be noted that the tapered sides 99 on the drain valve sleeve 9| guide the lower end of this sleeve between yoke arms I05 until the shoulder 9'! engages the upper edges of the yoke arms, after which the overflow tube 86 may again be twisted through 90 to lock flats between the yoke arms. It will thus be seen that if any of these parts require inspection, cleaning or replacement, they can be quickly and easily removed from the interior of the cabinet through the opened door 26, without disconnecting any part of the mechanism or otherwise dismantling the dishwasher, thus assuring desired ease of maintenance.

While the form of apparatus herein described constitutes a preferred embodiment of the in- Mention, it is to: be understood that the invention is notlimited to this precise form of apparatus, and that changesmay be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1 A dishwasher having a washing chamber adapted to receive articles to be washed, a sump atthe lower part of said chamber provided with accuses 7 a drain outlet in thelowerportion: thereof, a drain valve located at the bottom of said: sump. for controlling said outlet, operating: means for raising and lowering said valve to open and close. said outlet, means in said outlet below said. valve for connecting said valve to said operating means, said connecting means. being releasable upon rotational movement of said valve, a strainer including a portion extending downwardly within said'sump and completely enclos-- ing said drain outlet to effect collection of food particles immediately adjacent said outlet for discharge therethrough upon the opening of said valve, means in said sump for recirculating wash fluid through said chamber, a housing for said recirculating means located in saidsump, means accessible in said sump for removably securing said housing in position to facilitate ready removal thereof through said chamber to expose said recirculating means, an overflow tube lo cated in said sump and extending downwardly through said drain valve to provide an open connection to said outlet, means supporting said strainer for ready removal to expose said housing and said housing securing means, and means securing said overflow tube to said drain valve to form a handle for rotating, said, drain valve to releasesaid connecting means for removal of said tube. and drain valve asaunit.

2. A. dish washer having a washing chamber adapted to. receive. articles to be washed, a sump at. the lower part of said. chamber provided with a drain outlet in. the lower portion thereof, a drain valve located at thebottom of said sump for controlling said outlet, operating. means for raising and lowering said valve to open and close said'outlet, means in said. outlet below said valve for connecting. said valve to said peratingmeans, said connecting means being releasableupon rotational movement of said valve, means in said sump for. recirculating wash fluid through. said chamber, a. housing for said recirculating means located in said sump,. means accessible in said sump for removably securing said. housing in position to facilitate readyremoval, thereof: through said chamber. to. expose said recirculating means, an.overflow tube located in said. sump and extending. downwardly through said drain valve to provide. an open connection to said outlet, andmeans securing. said. overflow tube to said drain valve to form va handle for rotating said. drain valve to release said connecting means for removal of said tube.

anddrain valve. as a unit. 7 V V 3. A. dishwasher of the character described comprising'a cabinet, a casing mounted in said cabinet and forming a washing chamberv having an opening in the front. thereof and adapted to.

receive. articles to. be washed, a. door for said opening, said casing including aportion defining said impeller located in said space and including a, portion extending through said casing to form a driving support for saidv impeller adjacent the back of said sump, a housing for. said impeller 8 wardly extending portion forming a discharge passage from said impeller'and located substantially centrally of said chamber, means in the bottom of said sump forming a drain outlet from said chamber spaced forwardly from said impeller, a strainer adapted to be positioned between said sump and said chamber and including a depending perforate portion adapted to.

extend into said drain outlet to retain food particles for discharge through said outlet and to screen said particles from said housing intake passage, said strainer having an opening therein for receiving said upwardly extending housing portion, and means on said casing supporting.

said strainer for ready removal through said opening to provide access to said sump and saidimpeller.

4. A dishwasher of the character described comprising a cabinet, a casing mounted in said cabinet and forming a washing chamber having an opening in the front thereof and adapted to receive articles to be Washed, a door for said opening, said casing including a portion defining a sumpextending below said chamber bottom and located forwardlyof the center of said chamber to form. a space in said cabinet below said chamber and rearwardly of said sump, an impeller in said sump for recirculating wash fluid through said chamber, drive means for said impeller located in said. space and including a portion extending through said casing to form a driving support for said impeller adjacent the back of said sump, a housing for said impeller including a portion forming an intake passage thereto, means accessible in said sump through said opening for removably securing said housing to said casing, said housing includin an upward- 13/ extending portion forming a discharge passage from said impeller and located substantially centrally of said chamber, means in the bottom of said sump forming. a drain outlet from said chamber spaced forwardly from. impeller, a strainer including an upper portion adapted to be seated on said casing adjacent the top of said sump and including also. a depending perforate portion adapted to extend into said drainoutlet' to retain food particles for discharge through,

chamber having an opening in the front thereof, said casing includinga portion defining a sump located below and forwardly of the center of said.

chamber to form a'space. in said cabinet below said chamber and rearwardly of said sump, an.

impeller in said sump for recirculating wash fluid through said chamber, drive means for said impeller located in said. space and including a' portion extending through said casing to form v a driving supportfor said impeller adjacent the.

bacl; of said sump, a housing for. saidimp-ellei' mounted in said sump and. having an intake pas.-

j sage thereto, means inthebottom or saidsump. forming a drain outlet frem'sai'd chamber spaced forwardly from. said, impeller, a strainer. include ing an upper porticn adaptedlto' be seated; on

said casing adjacentlthe top. of said. sump and. including: also. a: depending: perforate portion;

adapted to extend into said drain outlet and having relatively small perforations to strain food particles from said impeller and retain said particles for discharge through said outlet, said housing including an upward extension forming a discharge passage from said impeller and located substantially centrally of said chamber, said strainer having an opening for receiving said housing extension, a Wash arm, means forming a removable support for said wash arm on said housing extension providing for rotation thereof in said chamber and for removal from said chamber to permit removal of said strainer, and a screen adapted to be removably seated in said strainer adjacent the top of said depending portion thereof and having large openings therethrough proportioned to retain material too large for discharge through said outlet, said screen being located forwardly of said housing extension to provide for removal thereof through said opening Without removal of said wash arm.

References Cited in the file of this patent UNITED STATES PATENTS Number 5 1,123,260 1,382,117 1,485,796 1,528,069 1,597,361 10 1,620,671 1,637,376 1,690,974 1,711,221 2,044,132 15 2,075,034 2,276,670 2,287,628 2,492,288

20 Number Name Date Dusseau Jan. 5, 1915 Opocensky June 21, 1921 Merseles et a1 Mar. 4, 1924 Merseles Mar. 3, 1925 Hazard et al. Aug. 24, 1926 Merseles Mar. 15, 1927 Gibney Aug. 2, 1927 Hazard et a1 Nov. 6, 1928 Blakeslee Apr. 30, 1929 Stoddard June 16, 1936 Grace et al Mar. 30, 1937 Reifenberg et a1. Mar. 17, 1942 McMahan June 23, 1942 Hollerith Dec. 27, 1949 FOREIGN PATENTS Country Date Germany May 13, 1911 

